<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <script src='./js/vue.js'></script>
	<title></title>
	
  
</head>

<body>
    <div id="app">
         <div id="app">
                
                <div :class="classObj"></div>
            </div>
    </div>

    
    <script>
        var vm = new Vue({
            el: '#app',
            data: {
                // 对象写法
                classObj: {
                   aa:true,
                   bb:true,
                   cc:true
                },

                // 数组写法
                classList: ['red', 'fontSize']
            },
        })

        Vue.set(vm.classObj, "dd", true)
        vm.$set(vm.classObj, 'ee', true)
        console.log(vm)
    </script>
</body>

</html>